SPF again (Re: XO Mail engineers?)

Crist Clark crist.clark at globalstar.com
Wed Aug 4 23:58:32 UTC 2004


Edward B. Dreger wrote:

> DAU> Date: Wed, 4 Aug 2004 15:46:17 -0700
> DAU> From: David A. Ulevitch
> 
> DAU> SPF's use of TXT records doesn't bother me so much.  It's
> 
> Perhaps some other technology would like to use TXT RRs.  If
> something hogs an entire RRTYPE at a given scope, it really
> should have its own RRTYPE.  An acceptable alternative would be
> KRB5-style "_foo" entries.  All IMHO.

Last time I looked, draft-ietf-marid-protocol-00.txt addressed this
issue,

2.1.1 DNS Record Type

    The record type is a textual RR type to be allocated by the IANA for
    this purpose.

    However, because there is a large number of domains with these
    records already deployed as TXT type records, and because there are a
    number of DNS server and resolver implementations in common use that
    cannot handle new RR types, the record type can be TXT.

    Domains SHOULD publish records under both types.  If a domain does
    publish under both types, then they MUST have the same content.

    Mail receivers SHOULD query for both types of records.  If both are
    returned, then the new RR type MUST be preferred.

    It is recognized that the current practice (using a TXT type record),
    is not optimal, but a practical reality due to the state of deployed
    records and software.  The two record type scheme provides a forward
    path to the better solution of using a RR type reserved for this
    purpose.

    For either type, the character content of the record is encoded as
    US-ASCII.

-- 
Crist J. Clark                               crist.clark at globalstar.com
Globalstar Communications                                (408) 933-4387



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